Researchers say they have a formula for divining which newborns are at highest risk of becoming obese during childhood.

With childhood obesity rates tripling over the last 30 years in the U.S., there is an urgent need to find better ways of curbing weight gain, and the earlier these efforts start, the better. So an international group of scientists have developed a model for predicting a child’s risk of developing obesity, which they hope will encourage parents to take early action to improve their children’s health.

“Many believe the critical time for the development of obesity is between ages zero and five—before kids go to school,” says lead study author Philippe Froguel, from the School of Public Health at Imperial College London. “Each year after age five is too late, and we wanted to find a way to predict the likelihood at birth. There are many non-genetic factors that are easy to analyze and are costless.”

To develop their formula, called the obesity risk calculator, the researchers analyzed data from the 1986 Northern Finland Birth Cohort that tracks a population of over 4,000 participants who were born in 1986. The scientists looked at five risk factors for obesity, including birth weight, body mass index (BMI) of the parents, the number of people in the newborn’s household, mother’s professional status and the mother’s smoking status during pregnancy. Each of these has been linked to obesity, either by promoting weight gain in a physiological or behavioral way; working mothers, for example, tend to make fewer meals at home, and their children are more likely to eat higher-calorie meals prepared at restaurants or in processed packages, while heavier parents may pass on obesity-related genes to their children.

The obesity risk calculator accurately predicted obesity rates among kids in the Finnish cohort, as well as two additional cohorts in Italy and the United States. About 20% of those kids predicted to have the highest risk for obesity accounted for 80% of all the childhood obesity cases. “Nobody has tried to make an equation to predict this before and I don’t know why,” says Froguel.

The researchers believe that having a simple tool to predict childhood obesity risk beginning at birth not only alerts physicians to children who are particularly vulnerable to weight gain, but provides an opportunity to motivate parents to keep their child’s health in check. The authors write:

Parents of newborns are particularly sensitive to information given about their child’s health. Once informed of their baby’s increased risk for obesity, they might be more receptive to routine advice provided from birth during the first two years of life within population-wide prevention: breast-feeding, feeding on demand, weaning no earlier than the sixth month with recommended meal patterns and food portions, avoiding of television and sugar-sweetened beverages.

“From my work in hospitals, I’ve been shocked by the lack of knowledge about nutrition, especially from young mothers. Even how to take care of the child if it’s crying,” says Froguel. “There is not enough education. New parents may think giving food to the child is the only way to get them to stop crying, but if you continue to do that the child could be overweight.”

Froguel envisions that the model may be used more as a teaching tool for health care experts than as a scare tactic for new parents. “If you scare the mom, it’s not useful, but for social workers and healthcare providers, it is a valuable education tool for high risk groups like new mothers, low income families and children with obese siblings,” he says.

He stresses that although the equation was successful in large populations in Finland, Italy and the U.S., it may need to be adjusted to more accurately reflect populations in different countries. “People don’t eat the same in every country, they don’t have the same culture. In some countries like Japan, the mothers are less likely to work or the people do not smoke. The equation works everywhere, but it cannot be the same equation for each country. We have to create predictions using different elements of an environment,” says Foguel.

Clinically, the equation could help caretakers to make weight maintenance a priority, but Dr. Stephen Pont, chair of the American Academy of Pediatrics Provisional Section on Obesity and a pediatrician at Dell Children’s Medical Center of Central Texas, says there is a critical need to take action now. “I think this can be helpful, however any child born today in America, the odds are that they will be challenged by their weight in the future. To some degree, the cards are already stacked against them,” says Pont. Having such a calculator in place for future generations, however, may ultimately contribute to earlier interventions and hopefully lower rates of obesity among children. “I do think these tools will be helpful to raise awareness. We see more and more research coming out showing the earliest impact we can have the better. Even having a mom who is a good weight before she is even pregnant can help.”